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Detailed Reference Information
Shervais et al. 1983
Shervais, J.W., Taylor, L.A. and Laul, J.C. (1983). Ancient crustal components in the fra mauro breccias. Journal of Geophysical Research 88: doi: 10.1029/JS088iS02p0B177. issn: 0148-0227.

Texturally pristine clasts preserve primary petrographic relationships and mineral compositions, yielding insights into igneous processes of the early lunar crust that cannot be gained from highly shocked and brecciated 'chemically pristime' samples. The use of texture as a prime criterion allows for expansion of the data derived solely from chemical criteria, and provides complementary data. Texturally pristine clasts from the Apollo 14 site studied here include anorthosite, troctolites, gabbronorites, and basalts. Alkali anorthosites are plagioclase orthocumulates and may form by flotation in Mg-suite plutons. Ferroan anorthosite was cataclastically deformed and metamorphosed to granulite facies. Troctolites include both O1+En+Plg cumulates. Major and trace element analyses of two troctolites reveal 'eastern' geochemical affinities that contrast other 'western' troctolites. Gabbronorites are Pig+Plg¿Sp cumulates whose parent magmas may range from high-Al to intermediate-Ti mare basalt. At least three varieties of mare basalt are found at Apollo 14: high-Al, low-Ti; low-Al, intermediate-Ti; and low-Al, Ti VHK basalt. VHK (Very High Potassium) basalt is a new variety indigenous to Apollo 14.

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Journal
Journal of Geophysical Research
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American Geophysical Union
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